Apparatus for testing components to be incorporated in a video cassette recorder

ABSTRACT

An apparatus for testing components to be inserted in a video cassette recorder or digital video cassette recorder includes a base provided with a pair of guide rails, a stationary plate, a first and a pair of second driven plates moving along the guide rails, and a capstan motor holder on which a capstan shaft and a hinge pin are mounted. The pinch roller lever assembly is provided with a pivot arm pivotably mounted to the hinge pin, a pinch roller rotatably mounted on the pivot arm, a lever and a coil spring, wherein one end of the lever is rotatably fixed near the pinch roller on the pivot arm and the other end is provided with a protrusion and a substantial ellipse-shaped ring, both ends of the coil spring are secured to the protrusion of the lever and the boss of the second driven plate, respectively.

This is a continuation, of application Ser. No. 08/618,740, filed Mar.20, 1996, now U.S. Pat. No. 5,700,960.

FIELD OF THE INVENTION

The present invention relates to an apparatus for testing components tobe incorporated in a video cassette recorder ("VCR") or a digital videocassette recorder ("DVCR"); and, more particularly, to the testingapparatus including a pinch roller lever assembly with a simplifiedstructure which enables a pinch roller therein to press a runningmagnetic tape against a capstan shaft without any malfunctioning.

DESCRIPTION OF THE PRIOR ART

In a manufacturing process of a VCR or a DVCR, certain components to beincorporated therein are usually tested before they are set therein.Particularly, in case of manufacturing a DVCR, based on the testing, itmay become necessary to change the size, inclination, position, etc. of,e.g., a head drum and a loading post. For the purpose, therefore, anapparatus for testing components to be incorporated in the VCR or DVCRis after used.

There is disclosed in Korean Utility Model Application No. 94-34267 suchan apparatus for testing components to be incorporated in a VCR or DVCR.

The prior art test apparatus includes a base 10 provided with a pair ofguide rails 11, a stationary plate 20, a first driven plate 40, a pairof second driven plates 50, 50', a pair of pole bases 30, a capstanmotor holder 80, a driving means 60 for reciprocating the first drivenplate 40 and hence the second driven plates 50, 50', and a pinch rollerlever assembly 90.

The guide rails 11 are spaced from and parallel to each other on thebase 10.

There are mounted on the stationary plate 20 a pair of reel tables 22and a head drum 21 including a rotary and a stationary drums.

Each of the second driven plates 50, 50' is interlocked to the firstdriven plate 40 through an elastic member 70.

On each of the pole bases 30, a pair of loading posts 31 is installedand the pole bases 30 are mounted on both inside surfaces of the seconddriven plates 50, 50', respectively.

In addition, there are fixed on the capstan motor holder 80 a capstanmotor (not shown) with a capstan shaft 27 and a hinge pin 81.

The pinch roller lever assembly 90 is provided with a pinch roller 26,an upper part 29 with a slot and a guide pin (not shown) protrudingdownwardly from a bottom surface thereof, a lower part 28 with aprotrusion, and a coil spring 33, wherein the pinch roller 26 isrotatably mounted on the lower part 28, the lower and the upper parts28, 29 are, in turn, pivotably mounted on the hinge pin 81 in such a waythat the protrusion is fitted into the slot and they are connected toeach other through the coil spring 33. Further, the guide pin of theupper part 29 is fitted into a guide groove 51 formed on the seconddriven plate 50' close to the capstan shaft 27.

When a tape cassette is loaded onto the reel tables 22, the first drivenplate 40, and hence the second driven plates 50, 50', move along theguide rails 11 by the driving means 60 in a forward direction asindicated with an arrow shown in FIG. 1. The pole bases 30 move to bothside positions adjacent to the head drum 21, respectively, according tothe movement of the second driven plates 50, 50', thereby wrapping amagnetic tape around the head drum 21.

On the other hand, as the second driven plate 50' moves, the guide pinof the pinch roller lever assembly 90 also moves along the guide groove51 thereon, thereby allowing the pinch roller lever assembly 90 to pivotabout the hinge pin 81 and enabling the pinch roller 26 to press themagnetic tape against the capstan shaft 27. This makes it possible tokeep a tape tension constant during the reproduction of signals recordedon the tape. During the reproduction process, a plurality of headsincorporated in the head drum read the signals, which are, in turn,displayed on a monitor (not shown) electrically connected to theapparatus.

As a result of the test, if desired, the position, inclination, height,size, etc. of certain components may be changed before they are set intothe VCR or DVCR.

However, in such a prior art test apparatus, the pinch roller leverassembly 90 has a large number of components so that it is ratherdifficult and cumbersome to put them together. In addition, the guidepin is apt to deviate from the guide groove on the second driven plate50' during a movement thereof, thereby preventing or hampering the pinchroller 26 from properly pressing the running magnetic tape against thecapstan shaft 27.

SUMMARY OF THE INVENTION

It is, therefore, a primary object of the invention to provide anapparatus for testing components to be incorporated in a VCR or DVCR,which includes a pinch roller lever assembly with a simplified structureenabling a pinch roller to press a running magnetic tape against acapstan shaft without any malfunctioning.

In accordance with one aspect of the present invention, there isprovided an apparatus for testing components to be incorporated in avideo cassette recorder or digital video cassette recorder, whichcomprises: a base provided with a pair of guide rails, wherein the guiderails are spaced from and parallel to each other on the base; astationary plate on which a pair of reel tables and a head drumincluding a rotary and a stationary drums are installed, the stationaryplate being mounted between the guide rails on the base; a pair of polebases on each of which a pair of loading posts is installed; a capstanmotor holder on which a capstan shaft and a hinge pin are mounted, thecapstan motor holder being mounted on the base; a first driven plate anda pair of second driven plates moving along the guide rails, wherein thepole bases are mounted on both inside lateral surfaces of the seconddriven plates, and, in response to a movement of the second drivenplates, move to both side positions adjacent to the head drum,respectively, and one of the second driven plates closer to the capstanshaft is provided with a boss; a driving means for reciprocating thefirst driven plate and hence the second driven plates; and a pinchroller lever assembly provided with a pivot arm pivotably mounted to thehinge pin, a pinch roller rotatably mounted on the pivot arm, a leverand a coil spring, wherein one end of the lever is rotatably fixed nearthe pinch roller on the pivot arm and the other end is provided with aholding means and a substantially ellipse-shaped ring, the boss of thesecond driven plate being inserted into the substantially ellipse-shapedring, both ends of the coil spring being secured to the holding means ofthe lever and the boss of said one of the second driven plates,respectively.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects and features of the instant invention willbecome apparent from the following description of preferred embodimentstaken in conjunction with the accompanying drawings, in which:

FIG. 1 shows a schematic top view of a conventional apparatus fortesting components to be installed in a VCR or DVCR;

FIG. 2 represents a schematic top view of the conventional testapparatus of FIG. 1, wherein the first and the second driven plates aremoved so as to have the pinch roller press the capstan shaft;

FIG. 3 illustrates a partial detailed top view of an apparatus fortesting components in accordance with a preferred embodiment of thepresent invention, mainly showing the pinch roller lever assembly; and

FIG. 4 depicts a partial detailed top view of the inventive testapparatus, wherein the pinch roller presses a running magnetic tapeloaded therein against the capstan shaft according to a movement of thesecond driven plates.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Although the main aspect of an apparatus for testing components to beinstalled in a VCR or DVCR in accordance with a preferred embodiment ofthe present invention is shown in FIGS. 3 and 4, FIGS. 1 and 2 will befrom time to time referenced in describing the inventive test apparatus.Furthermore, like reference numerals representing like components areused throughout FIGS. 1 to 4.

The inventive test apparatus includes a base 10 provided with a pair ofguide rails 11, a stationary plate 20, a first driven plate 40, a pairof second driven plates 50, 50', a pair of pole bases 30, a capstanmotor holder 80 and a driving means 60 for driving the first drivenplate 40 and the second driven plates 50, 50', and a pinch roller leverassembly 128.

The guide rails 11 are spaced from and parallel to each other on thebase 10.

There are installed on the stationary plate 20 a pair of reel tables 22and a head drum 21 including a rotary and a stationary drums. Thestationary plate 20 is mounted between the guide rails 11 on the base10.

Each of the second driven plates 50, 50' is interlocked to the firstdriven plate 40 through an elastic member 70. The second driven plate50' closer to the capstan shaft is provided with a boss 151.

The pole bases 30 are mounted on both inside surfaces of the seconddriven plates 50, 50', respectively. There are installed on each of thepole bases 30 a pair of loading posts 31 one of which is slanted.

The driving means 60 is provided with a motor 61, a worm wheel 62, and arack 63. The motor 61 has a worm 61', the worm wheel 62 being engagedwith the worm 61'. The rack 63 is mounted on the first driven plate 40,being engaged with the worm wheel 62 through an intermediate gear 62' atthe opposite side of the worm 61', and reciprocates in a longitudinaldirection thereof, thereby reciprocating the first driven plate 40 andthe second driven plates 50, 50'.

On the other hand, there are fixed on the capstan motor holder 80 acapstan motor (not shown) with a capstan shaft 27 and a hinge pin 130,and the capstan motor holder 80 is mounted between the guide rails 11 onthe base 10.

The pinch roller lever assembly 128 is provided with a pivot arm 131, apinch roller 132 rotatably mounted on the pivot arm 131, a lever 140 anda coil spring 133. The pivot arm 131 is pivotably mounted to the hingepin 130. One end of the lever 140 is rotatably fixed near the pinchroller 132 on the pivot arm 131 and the other end is provided with aprotrusion 141 and a substantially ellipse-shaped ring 142. It ispreferable that the ring 142 be integrally formed with the lever 140.The ellipse-shaped ring 142 has an inside space into which the boss 151of the second driven plate 50' is loosely inserted, and both ends of thecoil spring 133 are secured to the protrusion 141 of the lever 140 andthe boss 151 of the second driven plate 50, respectively, therebyallowing the pinch roller 132 to resiliently press a magnetic tapeagainst the capstan shaft 27 during the reproduction of signals recordedon the tape.

When a tape cassette is loaded onto the reel tables 22, the first drivenplate 40 and the second driven plates 50, 50', move along the guiderails 11 by the driving means 60 in a forward direction as indicatedwith an arrow shown in FIG. 1. In response to the movement of the seconddriven plates 50, 50', the pole bases 30 fixed thereto move to both sidepositions adjacent to the head drum 21, respectively, thereby having theloading posts 31 wrap a magnetic tape around the head drum 21. Duringthe movement of the second driven plates 50, 50', the boss 151 of thesecond driven plate 50' draws the lever 140 through the coil spring 133and pivots the pivot arm 131 so that the pinch roller 132 presses themagnetic tape against the capstan shaft 27, thereby keeping a tapetension constant during the reproduction of signals recorded on thetape. On the other hand, during the reproducing of signals, a pluralityof heads incorporated in the head drum assembly read the signals, whichare, then, displayed on a monitor (not shown) electrically connected tothe apparatus.

As a result of the test, if desired, the position, inclination, height,size, etc. of certain components such as the head drum 21 and theloading posts 31 may be changed before they are set into the VCR orDVCR.

The test apparatus of the present invention includes the simplifiedpinch roller lever assembly, thereby facilitating the assembly thereof.In addition, it enables the pinch roller to press the magnetic tapeagainst the capstan shaft without deviation of the guide pin from theguide groove as observed in the prior art.

Although the invention has been shown and described with respect to thepreferred embodiments, it will be understood by those skilled in the artthat various changes and modifications may be made without departingfrom the spirit and scope of the invention as defined in the followingclaims.

What is claimed is:
 1. An apparatus for testing components to beincorporated in a video cassette recorder, which comprises:a stationaryplate to which a capstan shaft and a stationary hinge pin are mounted; amoving plate; a pivot arm pivotally mounted to said stationary hingepin; a roller mounted on a first end of said pivot arm; and a leverpivotally fixed at a first end to said first end of said pivot arm, saidlever being resiliently and rotatably connected at a second end to saidmoving plate, wherein in a rest position said roller is disposed at apredetermined distance from said capstan shaft, said roller beingmovable to an engaged position when said moving plate is moved such thatsaid lever resiliently applies a force on said pivot arm to rotate saidpivot arm about said hinge pin to bring said roller into pressurecontact with said capstan shaft.
 2. The apparatus according to claim 1,wherein a resilient spring is secured at a first end to said lever andat a second end to said moving plate.
 3. The apparatus according toclaim 2, wherein said spring is secured to a boss disposed on saidmoving plate.
 4. The apparatus according to claim 3, wherein said levercomprises a ring at its second end, and wherein said boss is receivedinside said ring.
 5. The apparatus according to claim 4, wherein saidring has a substantially ellipse shape and is formed integrally withsaid lever.
 6. A pinch roller assembly for pressuring a magnetic tapeagainst a capstan shaft, said pinch roller assembly comprising:a pivotarm pivotally mounted to a stationary hinge pin; a roller mounted on afirst end of said pivot arm; and a lever pivotally fixed at a first endto said first end of said pivot arm, the lever being resiliently androtatably connected at a second end to a moving plate, wherein in a restposition the roller is disposed at a predetermined distance from thecapstan shaft, said roller is movable to an engaged position when saidmoving plate is moved such that the lever resiliently applies a force onsaid pivot arm to rotate said pivot arm about the stationary hinge pinto bring the roller into pressure contact with said capstan shaft. 7.The assembly according to claim 6, wherein a resilient spring is securedat a first end to the lever and at a second end to the moving plate. 8.The assembly according to claim 7, wherein the spring is secured to aboss disposed on the moving plate.
 9. The assembly according to claim 8,wherein the lever comprises a ring at its second end, and wherein saidboss is received inside said ring.
 10. The assembly according to claim9, wherein said ring has a substantially ellipse shape and is formedintegrally with the lever.